1 INTRODUCTION Reinforced concrete (RC) has been the most widely used structural system across the globe and the situa- tion is envisaged to continue in the next decades. However, it cannot be overlooked that RC system al- so comes with its own limitations where it may un- dergo deterioration and face reduction in its structur- al capacity over time. This can be due to various factors such as increased load intensity, weathering effects, the change of function of the building, mate- rial deterioration, etc. This gives rise to the need for structural retrofitting and strengthening works to be undertaken on these structures to ensure that their capacity meets the needs of the design. Over the last few decades, various external fac- tors such as increase in terrorist activities, accidental explosions and proliferation of weapons have result- ed in a new type of challenge to RC structures. These events result in the structure being exposed to extreme impulsive loadings, where most RC struc- tures in the civilian domain are not designed and constructed for. In view of this scenario, structural and material engineers are seeking novel and cost ef- fective protective solutions to mitigate the destruc- tion that may be caused by such extreme loading events. One approach to increase the resistance of structures to blast load is by increasing their mass and ductility. This can be accomplished by using ad- ditional concrete and reinforcement, or by using ex- ternal reinforcing techniques (such as carbon or glass fibre reinforced composites, or by using steel plates). However, the feasibility of external strengthening applications is usually restricted by limitations in the material’s technical capacity and the requirement for higher resources in installing them. In recent years, elastomeric polymers (such as polyurea) are finding relevance for strengthening and retrofitting applications of structures being subjected to blast, ballistic and impact loadings. Polyurea is an elastomeric polymer derived from the rapid reaction of an isocyanate component and a polyamine. The technique of using polyurea for structural retrofitting capitalises on the high strain capacity of the polymer, the composite action between the polymer and the structural material, as well as on the ability of the polymer layer to buffer the debris and fragments re- sulting from the blast event from propelling. This technique was explored for the first time by Knox et al. (2000) where they investigated feasibility of using the polyurea coating technique on masonry and lightweight steel structures subjected to blast loading. The positive findings from this initial exper- iment resulted in various researcher investigating the suitability of this innovative approach on masonry structures (Baylot et al. 2005, Davidson et al. 2004a, 2005), on steel structures and plates (Ackland et al 2013, Amini et al. 2010a,b, Chen et al. 2008) and on Retrofitting of RC panels subjected to blast effects using elastomeric polymer coatings S. N. Raman & M. Jamil Department of Architecture, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia T. Ngo & P. Mendis Department of Infrastructure Engineering, The University of Melbourne, Victoria 3010 Australia T. Pham Department of Civil and Industrial Construction, University of Civil Engineering, Hanoi 100000, Vietnam ABSTRACT: This paper presents the findings from the experimental programme and finite element (FE) analysis performed to study the behaviour of polyurea coated RC panels subjected to blast effects. The overall findings of the research, including detailed experimental findings of three of the tested panels (one un- retrofitted and two polyurea coated panels), and the subsequent FE analysis performed to simulate the blast trials, are discussed in this paper. All 3 panels had dimensions of 1700 (L)  1000 (W)  60 (T) mm. Among the retrofitted panels, one panel was subjected to a 4 mm polyurea coating on the non-blast facing face, whereas the other was coated with a 4 mm polyurea coating on both faces. All the panels were subjected to blast loads resulting from the detonation of 1.0 kg Ammonite charge placed at a 1.0 m stand-off. Identical panels were then modelled and analysed using the explicit solver of the non-linear FE code, LS-DYNA. The results from both experimental programme and FE analysis suggest that while the polymer coating technique does enhance the resistance of the RC panels to the applied blast load, a higher level of protection is provided when the protective coating is applied on the blast facing face of the structure.